High-Speed Internet Switches and Routers COMP 680E Mounir Hamdi Professor, Computer Science Director, MSc-IT Hong Kong University of Science and Technology
Goals of the Course • Understand the architecture, operation, and evolution of the Internet • IP, ATM, Optical • Understand how to design, implement and evaluate Internet routers and switches (Telecom Equipment) • Both hardware and software solutions • Get familiar with current Internet switches/routers research and development efforts • Appreciate what is a good project • Task selection and aim • Survey & solution & research methodology • Presentation • Apply what you learned in a small class project
Outline of the Course • The focus of the course is on the design and analysis of high-performance electronic/optical switches/routers needed to support the development and delivery of advanced network services over high-speed Internet. • The switches and routers are the KEY building blocks of the Internet, and as a result, the capability of the Internet in all its aspects depends on the capability of its switches and routers. • The goal of the course is to provide a basis for understanding, appreciating, and performing research and development in networking with a special emphasis on switches and routers.
Outline of the Course • Introduction • Definition and History of Networking/Internet • Evolution and Trends in the Internet • Architecture of The Internet • Classification and Evolution of Internet Equipment • Review and Evolution of Internet Protocols • Different technologies of the Internet
Outline of the Course • Network Processors: Table Lookup and Packet Classification • Internet addressing and CIDR • Table Lookup: Exact matches, longest prefix matches, performance metrics, hardware and software solutions. • Packet classifiers for firewalls, QoS, and policy-based routing; graphical description and examples of 2-D classification, examples of classifiers, theoretical and practical considerations • State-of-the-art commercial products
Outline of the Course • High-Performance Packet Switches/Routers • Architectures of packet switches/routers (IQ, OQ, VOQ, CIOQ, SM, Buffered Crossbars) • Design and analysis of switch fabrics (Crossbar, Clos, shared memory, etc.) • Design and analysis of scheduling algorithms (arbitration, Maximum/maximal matching, shared memory contention, etc.) • Emulation of output-queueing switches by more practical switches • State-of-the-art commercial products
Outline of the Course • Quality-of-Service Provision in the Internet • QoS paradigms (IntServ, DiffServ, Controlled load, etc.) • MPLS/GMPLS • Flow-based QoS frameworks: Hardware and software solutions • Stateless QoS frameworks: RED, WRED, congestion control, and Active queue management • State-of-the-art commercial products
Outline of the Course • Optical Networks • Optical technology used for the design of switches/routers as well as transmission links • Dense Wavelength Division Multiplexing • Optical Circuit Switches: Architectural alternatives and performance evaluation • Optical Burst switches • Optical Packet Switches • Design, management, and operation of DWDM networks • State-of-the-art commercial products
Grading • Homework 20% • Midterm 30% • Project 50%
Course project • Investigate existing advances and/or new ideas and solutions – related to Internet Switches and Routers - in a small scale project (To be given or chosen on your own) • define the problem • execute the survey and/or research • work with your partner • write up and present your finding
Course Project • I’ll post on the class web page a list of projects • you can either choose one of these projects or come up with your own • Choose your project, partner (s), and submit a one page proposal describing: • the problem you are investigating • your plan of project with milestones and dates • any special resources you may need • Final project presentation (~ 30 minutes) • Submit project papers
Homework • Goals: • Synthesize main ideas and concepts from very important research or development work • I will post in the class web page a list of “well-known” papers to choose from • Report contains: • Description of the papers • Goals and problems solved in the papers • What did you like/dislike about the paper • Recommendations for improvements or extension of the work
How to Contact Me • Instructor: Mounir Hamdi firstname.lastname@example.org • Office Hours • You can come any time – just email me ahead of time • I would like to work closely with each student
What is a Communication Network?(from an end system point of view) • A network offers a service: move information • Messenger, telegraph, telephone, Internet … • another example, transportation service: move objects • horse, train, truck, airplane ... • What distinguishes different types of networks? • The services they provide • What distinguish the services? • latency • bandwidth • loss rate • number of end systems • Reliability, unicast vs. multicast, real-time, message vs. byte ...
What is a Communication Network?Infrastructure Centric View • Hardware • Electrons and photons as communication data • Links: fiber, copper, satellite, … • Switches: mechanical/electronic/optical, • Software • Protocols: TCP/IP, ATM, MPLS, SONET, Ethernet, PPP, X.25, Frame Relay, AppleTalk, IPX, SNA • Functionalities: routing, error control, congestion control, Quality of Service (QoS), … • Applications: FTP, WEB, X windows, VOIP, IPTV...
Types of Networks • Geographical distance • Personal Areas Networks (PAN) • Local Area Networks (LAN): Ethernet, Token ring, FDDI • Metropolitan Area Networks (MAN): DQDB, SMDS (Switched Multi-gigabit Data Service) • Wide Area Networks (WAN): IP, ATM, Frame relay • Information type • data networks vs. telecommunication networks • Application type • special purpose networks: airline reservation network, banking network, credit card network, telephony • general purpose network: Internet
Types of Networks • Right to use • private: enterprise networks • public: telephony network, Internet • Ownership of protocols • proprietary: SNA • open: IP • Technologies • terrestrial vs. satellite • wired vs. wireless • Protocols • IP, AppleTalk, SNA
The Internet • Global scale, general purpose, heterogeneous-technologies, public, computer network • Internet Protocol • Open standard: Internet Engineering Task Force (IETF) as standard body • Technical basis for other types of networks • Intranet: enterprise IP network • Developed by the research community
1961: Kleinrock - queueing theory shows effectiveness of packet-switching 1964: Baran – Introduced first Distributed packet-switching Communication networks 1967: ARPAnet conceived and sponsored by Advanced Research Projects Agency – Larry Roberts 1969: first ARPAnet node operational at UCLA. Then Stanford, Utah, and UCSB 1972: ARPAnet demonstrated publicly NCP (Network Control Protocol) first host-host protocol (equivalent to TCP/IP) First e-mail program to operate across networks ARPAnet has 15 nodes and connected 26 hosts Internet History 1961-1972: Early packet-switching principles
1970: ALOHAnet satellite network in Hawaii 1973: Metcalfe’s PhD thesis proposes Ethernet 1974: Cerf and Kahn - architecture for interconnecting networks (TCP) late70’s: proprietary architectures: DECnet, SNA, XNA late 70’s: switching fixed length packets (ATM precursor) 1979: ARPAnet has 200 nodes Cerf and Kahn’s internetworking principles: minimalism, autonomy - no internal changes is required to interconnect networks best effort service model stateless routers decentralized control define today’s Internet architecture Internet History 1972-1980: Internetworking, new and proprietary nets
1971-1973: Arpanet Growing • 1970 - First 2 cross-country link, UCLA-BBN and MIT-Utah, installed by AT&T at 56kbps
1983: deployment of TCP/IP 1982: SMTP e-mail protocol defined 1983: DNS defined for name-to-IP-address translation 1985: ftp protocol defined (first version: 1972) 1988: TCP congestion control New national networks: CSnet, BITnet, NSFnet, Minitel 100,000 hosts connected to confederation of networks Internet History 1980-1990: new protocols, a proliferation of networks
Early 1990’s:ARPAnet decomissioned 1991:NSF lifts restrictions on commercial use of NSFnet (decommissioned, 1995) early 1990s: WWW hypertext [Bush 1945, Nelson 1960’s] HTML, http: Berners-Lee 1994: Mosaic, later Netscape late 1990’s: commercialization of the WWW Late 1990’s: est. 50 million computers on Internet est. 100 million+ users in 160 countries backbone links running at 1 Gbps+ 2000’s VoIP, Video on demand, Internet business RSS, Web 2.0 Internet History 1990’s: commercialization, the WWW
Growth of the Internet • Number of Hosts on the Internet: Aug. 1981 213 Oct. 1984 1,024 Dec. 1987 28,174 Oct. 1990 313,000 Oct. 1993 2,056,000 Apr. 1995 5,706,000 Jan. 1997 16,146,000 Jan. 1999 56,218,000 Jan. 2001 109,374,000 Jan. 2003 171,638,297 Jul 2004 285,139,107 Jul 2005 353,284,187 Today ~ 440,000,000 Source: http://www.isc.org/index.pl?/ops/ds/host-count-history.php
1997 22.5 Million Hosts 50 Million Users 2005 350 Million Hosts 1,018 Million Users Internet - Global Statistics (approx. 2.4 Billion Telephone Terminations, 660 Million PCs and 1.6B mobile phones)
Internet Penetration December 2006 (Source www.internetstats.com)
Top 10: % Internet Use (Dec 2006) www.internetworldstats.com
Who is Who on the Internet ? • Internet Engineering Task Force (IETF):The IETF is the protocol engineering and development arm of the Internet. Subdivided into many working groups, which specify Request For Comments or RFCs. • IRTF (Internet Research Task Force):The Internet Research Task Force is composed of a number of focused, long-term and small Research Groups. • Internet Architecture Board (IAB):The IAB is responsible for defining the overall architecture of the Internet, providing guidance and broad direction to the IETF. • The Internet Engineering Steering Group (IESG):The IESG is responsible for technical management of IETF activities and the Internet standards process. Composed of the Area Directors of the IETF working groups.
Internet Standardization Process • All standards of the Internet are published as RFC (Request for Comments). But not all RFCs are Internet Standards ! • available: http://www.ietf.org • A typical (but not only) way of standardization is: • Internet Drafts • RFC • Proposed Standard • Draft Standard (requires 2 working implementation) • Internet Standard (declared by IAB) • David Clark, MIT, 1992: "We reject: kings, presidents, and voting. We believe in: rough consensus and running code.”
Services Provided by the Internet • Shared access to computing resources • telnet (1970’s) • Shared access to data/files • FTP, NFS, AFS (1980’s) • Communication medium over which people interact • email (1980’s), on-line chat rooms, instant messaging (1990’s) • audio, video (1990’s) • replacing telephone network? • A medium for information dissemination • USENET (1980’s) • WWW (1990’s) • replacing newspaper, magazine? • audio, video (1990’s) • replacing radio, CD, TV? • 2000s: peer-to-peer systems – triple play bundles
Today’s Vision • Everything is digital: voice, video, music, pictures, live events, … • Everything is on-line: bank statement, medical record, books, airline schedule, weather, highway traffic, … • Everyone is connected: doctor, teacher, broker, mother, son, friends, enemies
What is Next? – many of it already here • Electronic commerce • virtual enterprise • Internet entertainment • interactive sitcom • World as a small village • community organized according to interests • enhanced understanding among diverse groups • Electronic democracy • little people can voice their opinions to the whole world • little people can coordinate their actions • bridge the gap between information haves and have no’s • Electronic Crimes • hacker can bring the whole world to its knee
Industrial Players • Telephone companies • own long-haul and access communication links, customers • Cable companies • own access links • Wireless/Satellite companies • alternative communication links • Utility companies: power, water, railway • own right of way to lay down more wires • Medium companies • own content • Internet Service Providers • Equipment companies • switches/routers, chips, optics, computers • Software companies
What is the Internet? • The collection of hosts and routers that are mutually reachable at any given instant • All run the Internet Protocol (IP) • Version 4 (IPv4) is the dominant protocol • Version 6 (IPv6) is the future protocol • Lots of protocols below and above IP, but only one IP • Common layer
local ISP local ISP regional ISP NBP B NBP A regional ISP NAP NAP Commercial Internet after 1994 • Roughly hierarchical • National/international backbone providers (NBPs) • e.g., Sprint, AT&T, UUNet • interconnect (peer) with each other privately, or at public Network Access Point (NAPs) • regional ISPs • connect into NBPs • local ISP, company • connect into regional ISPs
ISP ISP NAP BSP NAP BSP NAP BSP POP POP POP POP POP POP POP ISP CN CN CN CN CN CN CN CN Internet Organization ISP = Internet Service Provider BSP = Backbone Service Provider NAP = Network Access Point POP = Point of Presence CN = Customer Network
Commercial Internet after 1994 Joe's Company Berkeley Stanford Regional ISP Campus Network Bartnet Xerox Parc SprintNet America On Line UUnet NSF Network IBM NSF Network Modem Internet MCI IBM
Basic Architecture: NAPs and National ISPs • The Internet has a hierarchical structure. • At the highest level are largenationalInternet Service Providers that interconnect through Network Access Points (NAPs). • There are about a dozen NAPs in the U.S., run by common carriers such as Sprint and Ameritech, and many more around the world (Many of these are traditional telephone companies, others are pure data network companies).
The real story… • Regional ISPs interconnect with national ISPs and provide services to their customers and sell access to local ISPs who, in turn, sell access to individuals and companies.
pop pop pop pop
Node Node Node Node The Hierarchical Nature of the Internet Metro Network Long Distance Network Central Office Central Office San Francisco New York Major City - Regional Center Major City - Regional Center Central Office Central Office Central Office Central Office
POP3 POP2 POP1 D POP4 A B E POP5 POP6 C POP7 POP8 F Points of Presence (POPs)
Hop-by-Hop Behavior From traceroute.pacific.net.hk to cs.stanford.edu traceroute to cs.stanford.edu (126.96.36.199) from lamtin.pacific.net.hk (188.8.131.52), rsm-vl1.pacific.net.hk (184.108.40.206) gw2.hk.super.net (220.127.116.11) 3 wtcr7002.pacific.net.hk (18.104.22.168) 4 atm3-0-33.hsipaccess2.hkg1.net.reach.com (22.214.171.124) 5 ge-0-3-0.mpls1.hkg1.net.reach.com (126.96.36.199) 6 so-4-2-0.tap2.LosAngeles1.net.reach.com (188.8.131.52) 7 unknown.Level3.net (184.108.40.206) 8 lax-core-01.inet.qwest.net (220.127.116.11) 9 sjo-core-03.inet.qwest.net (18.104.22.168) 10 sjo-core-01.inet.qwest.net (22.214.171.124) 11 svl-core-01.inet.qwest.net (126.96.36.199) 12 svl-edge-09.inet.qwest.net (188.8.131.52) 13 184.108.40.206 (220.127.116.11) 14 sunet-gateway.Stanford.EDU (18.104.22.168) 15 CS.Stanford.EDU (22.214.171.124) Within HK Los Angeles Qwest (Backbone) Stanford
CHI NAP SF NAP NY NAP Sprint Net MAE West QWest MCI WDC NAP UUNET NAP-Based Architecture
Basic Architecture: MAEs and local ISPs • As the number of ISPs has grown, a new type of network access point, called a metropolitan area exchange (MAE) has arisen. • There are about 50 such MAEs around the U.S. today. • Sometimes large regional and local ISPs (AOL) also have access directly to NAPs. • It has to be approved by the other networks already connected to the NAPs – generally it is a business decision.